Polymers with a comb structure of pendant side chains are a new class of organic materials which exhibit interesting optical properties.
In U.S. Pat. Nos. 4,694,066; 4,755,574; and 4,762,912 polymers are described which have pendant side chains which exhibit nonlinear optical susceptibility, in addition to mesogenic properties.
U.S. Pat. No. 4,792,208 discloses nonlinear optically responsive organic compounds and side chain polymers in which the molecular dipoles have an electron donor moiety linked through a conjugated .pi. bonding system to an electron acceptor sulfonyl moiety.
U.S. Pat. No. 4,808,332 and U.S. Pat. No. 4,810,338 disclose polymers with pendant side chains in which a stilbene-type structure or a diphenylbutadiene-type structure is in conjugation with an electron-donating group and an electron-withdrawing group. These extended conjugated dipolar electronic systems exhibit an exceptionally high level of second order nonlinear optical susceptibility .beta..
Thin films of organic or polymeric materials with large second order nonlinearities in combination with silicon-based electronic circuitry have potential as systems for laser modulation and deflection, information control in optical circuitry, and the like.
Waveguide devices are being developed with are composed of a laminated matrix of nonlinear optically responsive polymeric waveguiding and cladding thin films on a supporting substrate. The polymeric thin films are difficult to form and maintain crack-free, and there is a tendency for a matrix of polymeric layers to delaminate because of weak adhesion between the layers.
There is continuing interest in the development of new and improved polymeric optical waveguiding systems.
Accordingly, it is an object of this invention to provide novel optically responsive polymers.
It is another object of this invention to provide acrylic copolymers having side chains which exhibit nonlinear optical response.
It is another object of this invention to provide nonlinear optically responsive thin films which form laminates with a high degree of bond strength between interlayers.
It is a further object of this invention to provide optical light switch and light modulator devices with a transparent polymeric nonlinear optical component comprising a thin film of an acrylic copolymer with nonlinear optically-responsive pendant side chains which can be uniaxially oriented to an external field.
Other objects and advantages of the present invention shall become apparent from the accompanying description and examples.